Navigation Links
Novel radiotracer shines new light on the brains of Alzheimer's disease patients
Date:6/24/2010

A trial of a novel radioactive compound readily and safely distinguished the brains of Alzheimer's disease patients from healthy volunteers on brain scans and opens the doors to making such imaging available beyond facilities that can manufacture their own radioactive compounds. The results, reported by a Johns Hopkins team in the June Journal of Nuclear Medicine, could lead to better ways to distinguish Alzheimer's from other types of dementia, track disease progression and develop new therapeutics to fight the memory-ravaging disease.

Previously, the only way to peer into the brains of Alzheimer's patients was through autopsy or the use of another radioactive compound used in scans, or radiotracer, known as Pittsburgh compound or PIB. PIB is drawn to a protein known as beta-amyloid, which accumulates abnormally in the brains of Alzheimer's patients. However, PIB has a half-life of only 20 minutes, meaning that half of the substance degenerates every 20 minutes after it is made. Consequently, PIB's use is possible only at a few hospitals or academic medical centers with facilities to manufacture it since this compound degenerates so rapidly.

To solve this conundrum, Dean F. Wong, M.D., Ph.D., a professor of radiology and psychiatry at the Johns Hopkins University School of Medicine, and his colleagues looked to a new radiotracer known as 18F-AV-45 (also known as florbetapir F18). This compound, based on the radioactive isotope fluorine-18, is drawn to beta-amyloid like PIB. However, unlike PIB, florbetapir has a half-life of about 110 minutes, greatly increasing its ability to be transported significant distances away from manufacturing facilities.

Testing the new compound for the first time in humans, Wong and his colleagues recruited 26 volunteers 11 previously diagnosed with Alzheimer's disease, and 15 healthy subjects of similar age who performed normally on cognitive tests. Each of these volunteers received an injection of florbetapir, then received a PET scan of their brains. The brain scans, acquired over a 90-minute period, allowed the researchers to see the uptake of florbetapir in the brain over time.

Florbetapir had significantly heavier accumulation in the Alzheimer's patients' brains compared to the healthy volunteers, collecting in brain regions expected to be high in beta-amyloid deposits based on previous research. The results in AD patients were readily distinguishable from those of healthy subjects by 30 minutes after injection, and the differences continued for up to at least 90 minutes after injection of florbetapir. None of the AD patients or healthy volunteers suffered any ill effects from florbetapir and showed normal vital signs, electrocardiograms and blood-work after the scan.

"We could easily tell apart the two groups of patients. Those without Alzheimer's disease retained much less of the compound, and those with Alzheimer's disease retained much more of it," Wong says. "This is the first time we've been able to get results like this with a compound that can travel beyond the confines of a major academic medical center to the majority of the U.S. population."

Wong adds that florbetapir's portability could lead to numerous applications for this compound. For example, though Alzheimer's disease can usually be diagnosed from neurocognitive tests, imaging with florbetapir could help settle tricky cases in which patients might have other forms of dementia instead. The compound may also be useful in future studies designed to help solve current medical mysteries, such as which patients are most likely to progress from mild cognitive impairment to full-blown Alzheimer's disease.

Florbetapir may also be useful in trials of new experimental Alzheimer's therapeutics to measure their success, a purpose for which this compound is already being used on a limited basis, Wong says.


'/>"/>

Contact: Christen Brownlee
cbrownlee@jhmi.edu
410-955-7832
Johns Hopkins Medical Institutions
Source:Eurekalert

Related medicine news :

1. Team led by LA BioMed scientist develops novel approach to study neurological disorders
2. Novel paclitaxel formulation encouraging for treating advanced lung cancer
3. Novel Drug Combats Advanced Melanoma
4. Novel RNA interference screening technique identifies possible path for malignant glioma treatment
5. Novel anti-malarial drug candidate found by UT Southwestern researchers
6. ASCO data highlight novel anti-cancer approach that exposes tumors to immune attack
7. Research identifies patterns of CD24, a novel biomarker for non-small cell lung carcinomas
8. Third European Novel Food Approval Received by Tahitian Noni International
9. Novel nanoparticles prevent radiation damage
10. Novel soy germ-based dietary supplement, SE5-OH containing natural S-Equol, examined for safety and influence on hormones in pre- and post-menopausal women
11. Novel Method Eyed for Normalizing Blood Sugar
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:9/26/2017)... ... ... The 2017 American Academy of Cosmetic Surgery World Congress on Liposuction meeting ... latest about cosmetic procedures to remove and replace fat, but also how stem cells ... is magical, especially when it comes to the cosmetic patient,” says cosmetic surgeon Dr. ...
(Date:9/26/2017)... ... ... Millennium”: a gripping take on how the author used personal experience to strengthen the ... do not affect daily choices. It shows how to act like the heirs of ... chosen. “How to Live in the Millennium” is the creation of published author, Gina ...
(Date:9/26/2017)... ... ... of My Song”: an intriguing and thought-provoking on love, life, and depression. “Sound of ... a passion for music and ancestral history. , Published by Christian Faith Publishing, ... depression, and finding love through the journey. There is powerful imagery in the poems ...
(Date:9/26/2017)... , ... September 26, 2017 , ... “The Tour Guide”: is the life story of ... the creation of published author, David Alexander Stark, is an adventure tour guide and the ... circled around to the back to confront fifteen shocked faces. I played it off as ...
(Date:9/26/2017)... ... 2017 , ... Time out for Daddy is a moving story of a ... grownups make mistakes. “Time Out for Daddy” is the creation of published author Debra ... whose passion for children inspired her to write this book. , Published by Christian ...
Breaking Medicine News(10 mins):
(Date:9/9/2017)... 8, 2017 Dealmed Medical Supplies, ... medical equipment, supplies, drugs, vaccines, and specialty medical products ... an agreement to acquire Vantage Medical Supplies, a major ... Holtsville, New York . ... and emerging medical practices, will operate under the Dealmed ...
(Date:9/7/2017)... , Sept. 7, 2017  Eli Lilly ... announced actions to streamline operations to more efficiently ... improve its cost structure. Global workforce reductions, including ... are expected to impact approximately 3,500 positions. ... company expects annualized savings of approximately $500 million ...
(Date:9/7/2017)... , Sept. 7, 2017 Caris ... focused on fulfilling the promise of precision medicine, ... validate the benefits of its molecular profiling approach ... utilized comprehensive genomic profiling plus (CGP+) with Caris ... patient,s tumor on a molecular level, leading to ...
Breaking Medicine Technology: